Method for accurately depositing a relatively small amount of a lip product on an applicator and the applicator containing said lip product

ABSTRACT

A method for depositing an amount of a heat meltable at room temperature non flowable semi-solid lip product ( 8 ) on an applicator having a flexible sheet-like support ( 1 ) with a lip product area ( 4 ) having an interconnected open channel structure, formed by channel forming elements ( 6 ), said area ( 4 ) having a circumferential raised edge ( 7 ), the method including depositing the amount of lip product in the lip product area ( 4 ), filling the lip product area ( 4 ) incompletely and/or non uniformly, subjecting the lip product ( 8 ) to a heat treatment to heat all of it to above the melting point thereof, such that the lip product ( 8 ) flows into the channel structure filling the lip product area ( 4 ) substantially complete and uniform, and cooling the assembly of applicator and lip product ( 8 ).

FIELD OF THE INVENTION

The present invention relates to a method for accurately depositing arelatively small amount of a lip product which is meltable by heat andwhich is non flowable at room temperature on an applicator forcontaining said lip product.

In the prior art a variety of methods is known for depositing a varietyof lip products on a variety of applicators. Said applicators rangingfrom relatively thin sheet-like supports to more rigid stick likeapplicators. All intended to contain and apply said lip product.

Lip products are usually quite vulnerable products which are easilysmeared or otherwise deformed even when still residing in the respectivepackage thereof and will thereby inadvertently be applied to the lipslater on.

The applicators which comprise a relatively small amount of a lipproduct are for example lip product samplers or testers, which are usedto enable potential customers to sample and try the lip product. Alsoencompassed are single use applicators for other purposes, like medicalpurposes.

SUMMARY

Lip products according to the invention are for example lipstick, orlipstick like materials and the like, but can also be medical products,like medical ointments, lip emollient, sun protection products, antiherpes labialis agent etc. The lip products used according to theinvention are non flowable and semi solid at room temperature which isintended to mean that they retain their three dimensional shape at roomtemperature and therefore also encompass products such as ointments andthe like. Products being liquid at room temperature are specificallyexcluded.

The lip product according to the invention has to be a heat meltable andnon flowable semi-solid at room temperature. Lipstick usually issupplied in bulk as a semi solid material which can be melted by heatand then becomes a liquid. When the liquid lipstick thereafter is cooledfor example in a mould it hardens to a harder consistency than beforeheating and melting.

When a relatively small amount of lip product is present on a support(applicator) intended for sample or testing purposes in the cosmeticsfield, it is very important that the material is deposited veryaccurately so that the applicator has the appearance of a rich productcomprising a lush amount of lip product, which is clean and whereby thelip product area has a circumferential delimitation which is as smoothand accurate as possible. The use of the applicator should be associatedwith quality and finesse. The lip product is intended to be applied tothe lips of a user, most frequently for cosmetic purposes, and thereforethe neat, accurate and glamorous appearance of the applicator comprisingthe lip product is of the utmost importance. Therefore the outline ofthe lip product area should be as meticulous as possible.

In the prior art no technique exists which can meet the above standards.Many lip product deposition techniques are described in the prior art.

According to U.S. Pat. No. 4,611,611 lipstick is applied on a papersheet by printing or first a lip product area is die stamped andthereafter printed. Finally the deposited lipstick is subjected to flamehardening whereby the surface of the lipstick is melted to provide a nonsmudging surface.

Further U.S. Pat. No. 4,747,782 discloses the application of lipstick ona paper support in a liquid state (melted) by spraying.

None of the prior at methods however provides an applicator with a lipproduct area which is very accurately and durably filled with lipproduct as described in the introductory part of the description.

In the prior art therefore a need exists to further improving theaccuracy of the deposition and thereby the appearance of the depositedlip product in the lip product area of a lip product applicator.

The present invention meets the above need by providing a method fordepositing a relatively small amount of a semi-solid lip product whichis meltable by heat and which is non flowable at room temperature on anapplicator for containing said lip product, said applicator comprising athin flexible sheet-like support with a surface with a lip product areawhich is designed to comprise the lip product, said lip product areacomprising an interconnected open channel structure therein, which isformed by channel forming elements, like for example small projectionsand/or cutouts, in the surface thereof, the lip product area of theapplicator having a circumference comprising a raised edge accuratelydelimiting said circumference and thereby forming a lip productreservoir, said raised edge having such dimensions that the lip productreservoir can at least accommodate the intended amount of lip product tobe deposited in the lip product area,

at least comprising the steps of

-   -   depositing the necessary amount of lip product in the lip        product area, such that the lip product area is filled        incomplete and/or non uniform,    -   subjecting the lip product to a heat treatment such that all of        the lip product is heated to above the melting point thereof,        all in such a manner that the lip product flows into the        interconnected open channel structure and thereby filling the        lip product area substantially complete and uniform, and    -   cooling the assembly of applicator and lip product.

The raised edge around the circumference of the lip product area forminga lip product reservoir in combination with the interconnected openchannel structure and the specific heat treatment wherein all of the lipproduct is heated to above the melting point thereof provides thesurprising effect that the lip product fills the entire lip product areaautomatically complete and uniform with high accuracy. The exactmechanism is not clear but it seems to be a combination of cohesive-,adhesive- and capillary forces. Also the hardened outer layer describedin the prior art is obtained, providing the necessary strength and shineto the lip product before use.

Per se US2009/0211591 discloses a multi-pattern lip cosmetic applicatorwhich comprises plural lip product reservoirs which are relatively smalland intended to contain different colours of lip product. The reservoirsmay also contain small projections extending and penetrating through thelip product for limiting the pressure of the lips against the lipproduct during the application process thereof. The lip product afterbeing applied can also be subjected to a heat treatment for forming ahardened surface thereof, which is common in the prior art.

However the specific combination of method steps according to theinvention providing the advantageous effect that the lip product fillsthe entire lip product area automatically very accurately complete anduniform is not disclosed.

The interconnected open channel structure is a channel structure whichis for a substantial portion accessible from the outside, and which ispreferably open to the surroundings for more than 50% of the surface ofthe lip product area covered by the channels, more preferably for morethan 80% and most preferred for substantially a 100% open. The channelsmay be formed by any suitable means, they may be engraved, embossed orthe like, or simply formed by injection moulding of projections and/orcutouts in the lip product area.

Also the raised edge is not specifically limited to a ridge or the likebut may for example also be the delimitation of a recess forming the lipproduct area, that is the connection of the recessed area with thehigher area. The raised edge is preferably substantially closed over theentire length thereof, and is therefore usually endless.

Compression of the applicator during use or storage is no problem as thepossible compression thickness is limited to the thickness of thechannel forming elements or projections and the raised edge. By properselection of the thickness of the channel forming elements orprojections, the raised edge and the amount of lip product smearing anddeformation by compression can be fully prevented.

Further because of the presence of the channel forming elements theamount of lip product can be decreased even further withoutdeterioration of the appearance of the applicator filled with lipproduct.

Finally the presence of the channel forming elements can be sensed bythe user on the lips which increases the accuracy of application of thelip product.

When lip product is applied to the lips using the applicator accordingto the invention the user can, as a consequence of the presence of thechannel forming elements, position the applicator on or between the lipsvery accurately.

The channel forming elements may be separate elements or form anintegral part of the applicator made by for example injection moulding.The channel forming elements preferably have a symmetrical shape andarrangement. The channel forming elements are designed and arranged suchthat many interconnected small open channels are formed. The channelforming elements can be separate elements attached or connected to theapplicator or may be formed in the applicator by embossing techniquesand the like in the material of the applicator itself. Examples ofchannel forming elements will be explained further with reference to theenclosed drawing.

The deposition of the lip product can as a consequence of the methodaccording to the invention be performed with methods having limitedaccuracy as long as the lip product is deposited inside the lip productarea, such as printing, screen printing, mask spraying etc.Advantageously the deposition of the lip product is performed by padprinting. The deposition accuracy can be low as practice has shown thatthe lip product after melting during the heat treatment will fill theentire lip product area accurately automatically without furtherhandling or method steps being necessary. The lip product just flows outtowards and against the raised edge. This advantageous covering effectof the lip product area with the lip product even takes place when theapplicator is held upside-down.

The heat treatment is preferably performed in a substantially horizontalposition of the applicator, whereby one face thereof is facing upwardand the other is facing downward. One or both of the faces of theapplicator may comprise a lip product area designed in accordance withthe present invention.

In particular during the heat treatment the assembly is shaken orvibrated in a substantially horizontal orientation. This has shown tofurther improve the covering effect of the lip product in the lipproduct area. Preferably the assembly is vibrated in the direction ofthe face of the applicator.

In an advantageous embodiment according to the invention the applicatorhas lip product areas on both sides, the lip product being deposited onboth sides thereof and preferably both sides being subjected to the heattreatment at the same time.

In a particular embodiment the applicator comprises a sheet-likeflexible support with a mouth end portion and an opposite positionedholding end portion, said sheet-like flexible support comprising on atleast one side thereof a lip product area carrying an amount of lipproduct, said lip product area being located on said support near themouth end portion thereof in such a manner that at least a substantialpart of at least one lip of a user can be brought into contact with saidlip product in said lip product area by taking the support between thelips at the mouth end portion, said support being dimensioned such thatit can be grasped manually at the holding end portion thereof whichduring use is located outside the mouth of the user, said sheet-likeflexible support being designed in such a manner that it has anincreasing flexibility from the mouth end portion to the holding endportion at least over the part of the lip product area of the supportcarrying the lip product.

The above applicator is disclosed in WO-A-2007/006559. This applicatorprovides outstanding results in applying lipstick to the lips of a userin an extremely accurate manner. The present invention provides asubstantial improvement to the above applicator as with the methodaccording to the invention including the minor adjustments to the lipproduct area, comprising the addition of the channel forming elementsand the raised edge, a perfect product is obtained fully meeting thehigh accuracy standards required for such products in the cosmeticsfield.

Advantageously said sheet-like flexible support has a substantiallytriangular shape with rounded corners and has a substantially constantthickness, and the lip product area being designed in a curved band neara base of the triangular shape in order to approach the curvature of thelips of a user when used. This embodiment will be discussed in greaterdetail with reference to the enclosed drawings.

Finally the invention provides an applicator obtainable with the methodaccording to the invention. Preferably the channel forming elements inthe lip product area have rounded top edges. This has the advantage thatduring the heat treatment these curved or rounded top edges will be leftuncovered. This means that when the applicator is in a package betweenfoils or the like the lip product does not substantially touch thepackage as this is only in contact with the top edges of the channelforming elements.

The invention also relates to a method for depositing a relatively smallamount of a heat meltable at room temperature non flowable semi solidlip product on an applicator for containing said lip product, saidapplicator comprising a thin flexible sheet-like support with a surfacewith a lip product area which is designed to comprise the lip product,said lip product area comprising an interconnected open channelstructure therein, which is formed by channel forming elements, like forexample small projections and/or cutouts, in the surface thereof, thecircumference of the lip product area of the applicator comprising araised edge accurately delimiting said circumference, having suchdimensions that it can at least accommodate the intended thickness ofthe lip product to be deposited in the lip product area,

at least comprising the steps of

-   -   depositing the necessary amount of lip product in the lip        product area,    -   subjecting the lip product to a heat treatment, such that all of        the lip product is heated to above the melting point thereof,        and    -   cooling the assembly of applicator and lip product.

Preferably this method is further characterized in that

-   -   the necessary amount of lip product is deposited in the lip        product area with limited accuracy, and    -   the lip product is subjected to a heat treatment such that all        of the lip product is heated to above the melting point thereof,        all in such a manner that the lip product will fill the channels        between the channel forming elements up against the raised edge        of the lip product area.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following the invention will be explained in greater detail withreference to the accompanied drawings, therein:

FIG. 1 shows a planar view of an applicator suitable for use with themethod according to the invention;

FIG. 2 shows a magnified schematic view of a portion of thecross-section I-I from FIG. 1 wherein the lip product area is filledwith lipstick; and

FIGS. 3 a-3 g show seven embodiments of the open channel structure withdifferent channel forming elements.

DETAILED DESCRIPTION

FIG. 1 shows an applicator according to the invention comprising asheet-like support 1 with a mouth end portion 2 and a holding endportion 3. Near the mouth end portion 2 a lip product area 4 is present.Near the holding end portion 3 a triangular opening 5 is present forimproving the grip when using the applicator. The applicator can be madefrom many different materials but is preferably injection moulded fromplastic like for example polypropylene or polystyrene.

The lip product area 4 comprises an interconnected open channelstructure being composed of channel forming elements 6 having the shapeof small sticks. 100% of the interconnected channel structure is open tothe surroundings. The entire lip product area 4 is designed as a recessin the sheet-like support 1. The circumference 7 of the recessed lipproduct area 4 is formed by a raised edge delimiting said lip productarea 4 as a lip product reservoir. In this embodiment intended for usewith especially lipstick the underside of the applicator is designedsimilarly and on both sides the lip product areas 4 or reservoirs can befilled with lipstick, which will be described in connection with FIG. 2.

FIG. 2 shows a magnified schematic cross-section of the applicator shownin FIG. 1. 8 denotes lipstick deposited in the respective lip productareas 4. Lipstick can be deposited on both sides at the same time. Themethod according to the invention comprises the following steps.

First the applicator according to FIG. 1 is transported to a padprinting arrangement wherein the applicator is on both sides in aninaccurate manner provided with an amount of lipstick 8 by pad printing.The pad printing method does not have to be very accurate as long as therequired amount of lipstick 8 is deposited inside the lip product areas4 roughly following the shape of the inner circumference of the lipproduct areas 4. Then the applicator comprising lipstick 8 on both sidesinside the respective lip product areas 4 is conveyed into a heatingchamber in which the entire assembly is heated such that the lipstick isbrought to a temperature above the melting point thereof, preferablywith forced air heating. During the heating the applicator istransported in a substantial horizontal fashion and is vibrated with arelatively low frequency in the direction of the face of the applicatorwhile the applicator is held in a substantially horizontal orientation.A low frequency is a frequency of below 50 Hz, preferably below 25 Hzand most preferred around 10 Hz.

After a suitable heating time depending on the temperature of theheating chamber, the melting point and the amount of the lipstick 8,such that all the lipstick 8 is in a melted state, the applicator istransported out of the heating chamber and allowed to cool. Said coolingmay be forced cooling.

The actual heating temperature is not limited to the melting point ofthe lip product and can be much higher as long as the duration of theheat treatment is adapted thereto and the favourable effects of thepresent invention are obtained.

As a consequence of the presence of the small interconnected channelsbetween the channel forming elements 6 during heating when the lipstick8 is completely melted the lipstick will display an automatic coveringeffect. It flows out to fill the channels between the channel formingelements 6 up against the circumferential raised edge 7 of the lipproduct area 4 or reservoir.

In FIG. 2 it can be clearly seen that the rounded tips of the channelforming elements 6 stay free from lipstick 8. This is advantageous whenlater on when the applicator is packaged the packaging material willcome in contact with substantially only the material of the applicatoritself and not with the lipstick.

It will be clear that the specific practical embodiment of the lipproduct area or reservoir with the raised edge and the interconnectedchannel structure is not limited and that many variations thereof may beused. A recessed lip product area is not necessary as the raised edgemay also be formed in the shape of a circumferential ridge orprotrusion.

FIG. 3( a-g) show seven different embodiments of possible interconnectedchannel structures formed by channel forming elements. FIG. 3( d) is theembodiment used in FIG. 1.

When using the applicator the mouth end portion 1 of the applicator willbe positioned inside the mouth and the lips brought into contact withthe respective lip product areas 4. This can be done by grabbing theapplicator with the fingers of one hand at the holding end portion 3preferably at the location of the opening 5 for improving alignment ofthe applicator with the mouth. By bending the applicator up and downlipstick 8 is transferred from the lip product areas 4 onto the lips.During bending the channel forming elements 6 exert a mixing action onthe lipstick, whereby the transfer thereof is further improved.

What is claimed is:
 1. A method for depositing a semi-solid lip product(8) which is meltable by heat and which is non flowable at roomtemperature on an applicator for containing said lip product (8), saidapplicator comprising a thin flexible sheet-like support (1) with asurface with a lip product area (4) which is designed to comprise thelip product (8), said lip product area comprising an interconnected openchannel structure therein, which is formed by channel forming elements(6) in the surface thereof, the lip product area (4) of the applicatorhaving a circumference comprising a raised edge (7) accuratelydelimiting said circumference and thereby forming a lip productreservoir, said raised edge (7) having such dimensions that the lipproduct reservoir can at least accommodate the lip product (8) to bedeposited in the lip product area (4), the method comprising the stepsof: depositing the lip product in the lip product area (4), such thatthe lip product area (4) is filled incompletely and/or non uniformly,subjecting the lip product (8) to a heat treatment such that all of thelip product (8) is heated to above the melting point thereof, all insuch a manner that the lip product (8) flows into the interconnectedopen channel structure and thereby filling the lip product area (4)substantially completely and uniformly, and cooling the assembly ofapplicator and lip product (8).
 2. The method according to claim 1,wherein depositing the lip product (8) is performed by pad printing. 3.The method according to claim 1, further comprising, during the heattreatment shaking or vibrating the assembly in a substantiallyhorizontal orientation.
 4. The method according to claim 1, wherein theapplicator has lip product areas (4) on both sides and the lip product(8) is deposited on said both sides and that both sides are subjected tothe heat treatment at the same time.
 5. Applicator obtainable with themethod according to claim
 1. 6. The applicator according to claim 5,wherein the channel forming elements (6) in the lip product area haverounded top edges.
 7. A method for depositing an amount of semi-solidlip product (8) which is meltable by heat and which is non flowable atroom temperature on an applicator for containing said lip product (8),said applicator comprising a thin flexible sheet-like support (1) with asurface with a lip product area (4) which is designed to comprise thelip product (8), said lip product area comprising an interconnected openchannel structure therein, which is formed by channel forming elements(6) in the surface thereof, the circumference of the lip product area(4) of the applicator comprising a raised edge (7) accurately delimitingsaid circumference, having such dimensions that it can at leastaccommodate an intended thickness of the lip product (8) to be depositedin the lip product area (4), the method comprising the steps of:depositing the amount of lip product in the lip product area (4),subjecting the lip product (8) to a heat treatment, such that all of thelip product (8) is heated to above the melting point thereof, andcooling the assembly of applicator and lip product (8).
 8. The methodaccording to claim 7, wherein the amount of lip product is deposited inthe lip product area (4) with limited accuracy, and the lip product (8)is subjected to a heat treatment such that all of the lip product (8) isheated to above the melting point thereof, all in such a manner that thelip product (8) fills the channels between the channel forming elements(6) up against the raised edge (7) of the lip product area (4).